Many other things did happen on this date in history, and it has only been a century since the birth of the author of one major event. This date does get celebrated by numerous RWNJs.
By April 1945, Soviet troops were closing in on Berlin. The city was frequently bombed, which meant that even garden strolls could be dangerous. Hitler stayed inside the Führerbunker for longer stretches of time. On April 20, he spent his 56th birthday there. It would be the last one he ever celebrated.